A PAIR OF PLIERS

Abstract: A pair of circlip pliers, for mounting or dismounting of circlips, comprising two jaws each having a first side (11, 13) arranged to be pressed against a hole of an end of the circlip during deformation of the circlip for mounting or dismounting purposes. The first side (11, 13) of each jaw is provided with a non-symmetrical waist (16) forming a part of a rational surface having an axis (17) of symmetry spaced from the axis (18) of the jaw and that the distance is so large that no undercut arises at the contour of the second side (12, 14).

Description: A PAIR OF PLIERS Background of the invention A circlip is used for axially locking a component to an axis or a pipe. The ends of the circlip are enlargened and provided with holes to facilitate mounting by means of a circlip pliers. The jaw tips of the pliers are entered into the holes. A circlip for external positioning is mounted by separating the ends until the inner diameter of the circlip becomes large enough to enter the axis. A circlip for internal positioning is mounted by reducing the gap between the ends until the outer diameter of the circlip becomes short of the diameter of the hole in the pipe thereby making insertion therein possible. The dismounting process is reverse to the mounting process. Different pliers are used for external and internal positioning. True in both cases of pliers is that a circlip held by the pliers is charged with a large amount of elastic energy, such that it easily may fly away if one end slides off of one tip of the jaws. This can easily happen if the tips are smooth and conical. Thus conventional solutions rely on tips with waists or tips with splines increasing friction to prevent the circlip from sliding. The circlip will in connection with the conventional pliers, be held to the jaws even when one has let go of the operating grip of the jaws. That may extend the time for mounting and may demand that both hands be used to put the circlip aside for temporary storing during disassemblying of a machine element. A prior art tool shown in Fig. 4 have jaws with tips that each includes a symmetrically shaped waist 15. The waist however prevents the circlip from sliding along both sides of the jaw and thus impedes the dismounting process. CONFIRMATION Y Object of the present invention The present invention relates to a pair of circlip pliers having tips of the jaws configured in a manner that mounting and dismounting of circlips are facilitated. Description of the drawings Fig. 1 shows a pair of circlip pliers according to the present invention for internal mounting; Fig. 2 shows a pair of pliers according to the present invention for external mounting; Fig. 3 shows a tip of a jaw of a pair of pliers according to the invention and Fig. 4 shows a tip of a jaw of a prior art tool. Detailed description of the preferred embodiments of the invention When using a pair of circlip pliers as shown in Fig. 1 for internal mounting of a circlip it is desirable that the hole of the circlip may slide along the outer side 11 of the jaw but not along its inner side 12. When using a pair of circlip pliers as shown in Fig. 2 for external mounting of a circlip it is desirable that the hole of the circlip may slide along the inner side 13 of the substantially conical jaw but not along its inner side 14. Fig. 3 shows an alternative embodiment according to the present invention, wherein each jaw has been provided with a non-symmetrically placed waist 16. The waist is preferably arranged as an imaginary part of a turned or ground rotational surface having an axis 17 of symmetry different from the symmetry axis 18 of the jaw. The side 12, 14 of the jaw along which the circlip is not supposed to slide along thereby achieves an undercut contour while the side 11, 13 of the jaw along which the circlip is supposed to slide along, remains smooth or is partly conical with a conicity 19 steeper that that of the jaw. As an alternative shape the non-symmetrical waist may be described by a very large radius thereby closing on to a substantially planar undercut. Circlip pliers according to the present invention may be provided with conventional straight or bent jaws with or without a contra-acting spring. Thus the present invention relates to a pair of pliers for mounting or dismountiong of circlips comprising two jaws, each having a first side 11, 13 arranged to be pressed against a hole of an end of the circlip during deformation of the circlip for mounting or dismounting purposes, said jaw having a second side 12, 14 pressing against said hole during release of the pliers. The first side 11, 13 of each jaw which can touch the circlip is provided with a non-symmetrical waist 16 forming a part of a rotational surface having an axis 17 of symmetry spaced from the axis 18 of symmetry of the jaw. The distance is so large that no undercut arises at the contour of the second side 12, 14. Each jaw is generally conical and the tip of the jaw is conical but with an included angle larger than the corresponding angle of the jaw.

Claims: Claims 1. A pair of pliers for mounting or dismountiong of circlips comprising two jaws, each having a first side (11,13) arranged to be pressed against a hole of an end of the circlip during deformation of the circlip for mounting or dismounting purposes, said jaw having a second side (12,14) pressing against said hole during release of the pliers characterized in that the first side (11,13) of each jaw which can touch the circlip is provided with a non-symmetrical waist (16) forming a part of a rotational surface having an axis (17) of symmetry spaced from the axis (18) of symmetry of the jaw and that the distance is so large that no undercut arises at the contour of the second side (12,14). 2. A pair of pliers according to claim 1, characterized in that each jaw is generally conical and that the tip of the jaw is conical but with an included angle larger than the corresponding angle of the jaw.

Inventors: JANSSON CONNY, JANSSON, CONNY
Applicants: JANSSON CONNY, SANDVIK AB, JANSSON, CONNY
Application year: 1994
Main classification: B25B27
IPC codes: B25B27